1957 Gaggia America 1 group - Page 2

A haven dedicated to manual espresso machine aficionados.
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Paul_Pratt (original poster)
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#11: Post by Paul_Pratt (original poster) »

cafebmw wrote:wow! another great job of yours!
where do you get those machines? here in the US vintage commercial machines are very rare.
From Europe mainly, some from Australia. I have been looking for ages and a few came along at once. Once you can get the shipping sorted the transactions are relatively painless. Oh and of course you take an enormous gamble.

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Paul_Pratt (original poster)
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#12: Post by Paul_Pratt (original poster) »

drgary wrote:Paul,

Keep on posting. I always enjoy seeing your museum quality work, which gives a close-up view of these golden era treasures and restoration tutorials that are unequalled.

I've got a technical question and hesitate to ask this of a master restorer. But what the heck, I value your opinion. I wondered why you chose citric acid for descaling the manometer rather than vinegar? Our resident chemist (rpavlis) contributed this post awhile back:
Thanks for that I had not seen it before. I mainly use citric because it is available to me. Will give that a try next time.

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dmccallum
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#13: Post by dmccallum »

Last week before chrome I had to make a small valve that controls the infusion rate of the water entering in the group. The original was absolutely shot as someone tried to get it out by brute force. Here's the broken original and my new one.
Hi Paul

One of my grouphead valves has a damaged thread that prevents it from completely closing the flow off (I'm assuming it's supposed to be able to?). I'm hoping I can rectify with tap & die.
What's the thread size&pitch ? It looks to be fine.

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Paul_Pratt (original poster)
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#14: Post by Paul_Pratt (original poster) »

Should be 1/8 bsp

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Paul_Pratt (original poster)
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#15: Post by Paul_Pratt (original poster) »

A little update. I had to use a Faema lever a few weeks back and was immediately struck by the better shots the Faema was making compared to the Gaggia. So I have spent the past week or so adjusting the Gaggia group.

The first improvement was using a bottomless portafilter, it helps if you make your own :D



After that I took the group apart and cleaned it all again. Since this was a functional rebuild with no chrome plating involved it is difficult to get the metal clean and I could smell that the shots were a little dirty. So I cleaned all the parts again.

I then had a look at the group dispersion screen, the Gaggia screens are pretty basic and they spray water out into a donut shape since the edges are open. I had a go, as one does, at making a new screen with enclosed sides that would hopefully stream the water downwards rather than out the sides.

Here is my stainless steel screen. The side facing up presses against the piston.





Yeah that didn't work either :roll: So in the end I tried a Faema screen that required a different gasket but went in eventually.



Much better water dispersion! Nice and even. The shots have been much better already, a marked improvement I must say. The spent pucks are also uniform and intact rather than the uneven soggy mess they were before.

I have had some great looking and tasting shots over the past few days. A very worthwhile modification if you ask me.


kitt
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#16: Post by kitt »

Nice work!! I"ve never liked the original shower screen set-up either and had messy soggy pucks also. Is the new shower screen set-up static and held in place by the group gasket, rather than attached to the piston like the old shower screen? This would also help reduce seal contamination you could get with the old system as the shower screen exposed the seals during extraction.

I've also seen that E61 shower screen adapted for the Faema curvy early lever group, to replace the clip-on style.Can be a handy mod especially if the lip on the group sleeve is damaged as it was on mine

Sansibar99
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#17: Post by Sansibar99 »

Great modification, Paul!
Would you share the information on the gasket you are using with the E61-screen?
I really am thinking of making that same tweak ;-)

Thank you for sharing!

Cheers,
Holger
LMWDP #422

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Paul_Pratt (original poster)
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#18: Post by Paul_Pratt (original poster) »

The screen is held in place by the gasket. The gasket is a standard E61 8.5mm but made from silicone rather than hard rubber so it was able to fit. I shall have news on the silicone gaskets shortly.

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gyro
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#19: Post by gyro »

The other alternative appears to be an o-ring or gasket under the shower screen to effectively block the sides as Marcio posted. I need to remedy mine whichever way is the easiest - on my first tests with the machine up to pressure the water dispersion was a quite strong and a horrible donut pattern... totally around the edges with nothing whatsoever in the middle.

http://www.youtube.com/watch?v=pmKEMMe14Qk

Are your Gaggia PFs ready yet?? I'm heading south in a week and would love to buy 3 if they are good to go?

Cheers, Chris

walshman
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#20: Post by walshman »

Fantastic. I wish I had the knowledge and skill that you have Paul.